For coding agents, GPT-5.5 costs 3.1x as much as Grok 4.3 per request ($0.21 vs $0.068 on our measured traffic), because GPT-5.5 lists at $5 input, $0.50 cached input and $30 output per million tokens against $1.25, $0.20 and $2.50 for Grok 4.3, and both charge more for long prompts.
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| Cost at list price | Grok 4.3 | GPT-5.5 |
|---|---|---|
| Prompt under 100K tokens50% of requests, 87% of input cached | $0.021 | $0.081 |
| Prompt of 100K to 272K39% of requests, 88% of input cached | $0.077 | $0.20 |
| Prompt over 272K tokens11% of requests, 86% of input cached | $0.26 | $0.86 |
| Average request | $0.068 | $0.21 |
| 100 requests | $6.84 | $20.99 |
| Median session16 requests; a session ends after 10 idle minutes | $0.61 | $2.30 |
| A month of regular usemedian of 20 users active on 5+ days | $103 | $296 |
Each logged request priced at the vendor’s list rates for its own token counts, including cache reads and any higher rate for long prompts. Average output: 698 tokens per request.
| Artificial Analysis | Grok 4.3 | GPT-5.5 |
|---|---|---|
| Intelligence Index10 evaluations, 0 to 100 | 25 | 38 |
| Terminal-Bench 4.0agentic coding in a terminal | 0.0% | 14.6% |
| Output speedmedian | 113 tokens/s | 105 tokens/s |
| Time to first answer tokenincludes thinking time | 25 s | 71 s |
Source: Artificial Analysis (artificialanalysis.ai). Measured variants: Grok 4.3 (High), speed on SpaceXAI; GPT-5.5 (Xhigh), speed on OpenAI. Fetched October 13, 2026. Artificial Analysis runs Terminal-Bench 4.0 in its own setup, so its scores differ from the tbench.ai leaderboard.
GPT-5.5 is superseded: GPT-6.1 Sol costs $0.067 per request. Grok 4.3 is superseded: Grok 4.7 costs $0.13 per request. GPT-5.5 scores clearly higher on the benchmarks above, so it may finish hard tasks in fewer steps.
Pick a winner in each dimension. You can change your vote any time.
Correctness and depth of what it produces
Tool calls, instruction-following, and multi-step tasks
Tokens per second and time-to-first-token
How much capability you get per dollar
Consistent results: fewer refusals, loops and format breaks
Setting it up? Grok 4.3: model ID, providers and agent config
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Current Claude, GPT, Gemini and open models run on Standard Compute